Regardless of whether or not there's an actual need for pedestrian warning systems for hybrid and electric vehicles, the U.S. Senate has voted unanimously to approve a measure that would make the noise-adding setup standard on all vehicles that can operate – even if just momentarily – without the burble of an engine.

The measure, called the Pedestrian Safety Enhancement Act of 2010 and backed by Democratic Sen. John Kerry of Massachusetts, aims to establish standards for alerting pedestrians of the possible danger of an approaching vehicle that moves in near silence. With the Senate voting in favor of the bill, it will now head off to the House of Representatives, where it's expected to pass with ease.

[Source: Green Car Advisor]